It is known to provide switched digital services via two-wire telephone channels. Modern digital services, for example, are capable of providing switched digital rates of up to 160 Kbps. A typical problem with providing such service, however, is that the telephone line may include a bridge-tap on the line. This bridge-tap results in a received signal that includes an amount of bridge-tap distortion.
In the past, the compensation for bridge-tap distortion on lower speed lines has consisted of implementing an echo cancellation stage in a digital signal processor ("DSP"). While a DSP solution provides adequate compensation for bridge-tap line connections at the voice and lower speed modem frequencies, the DSP approach is not a cost-effective solution at the 160 Kbps switched digital rates due to the clock speed required to provide the necessary sampling rate.
As a result, there is a need to provide a hardware-based bridge-tap equalizer that is capable of compensating for bridge-tap distortion at rates of 160 Kbps.